leetcode.com 129. Sum Root to Leaf Numbers

문제 링크: https://leetcode.com/problems/sum-root-to-leaf-numbers

Author: skysign

leetcode.com 129. Sum Root to Leaf Numbers/main.py

@@ -0,0 +1,29 @@
+from typing import Optional
+
+
+# Definition for a binary tree node.
+class TreeNode:
+    def __init__(self, val=0, left=None, right=None):
+        self.val = val
+        self.left = left
+        self.right = right
+
+
+class Solution:
+    def __init__(self):
+        self.answer = 0
+
+    def sumNumbers(self, root: Optional[TreeNode]) -> int:
+        self.dfs(root, 0)
+        return self.answer
+
+    def dfs(self, node: Optional[TreeNode], v):
+        if node.left is None and node.right is None:
+            self.answer += (v * 10 + node.val)
+            return
+
+        if node.left:
+            self.dfs(node.left, v * 10 + node.val)
+
+        if node.right:
+            self.dfs(node.right, v * 10 + node.val)